Our recent Facebook post about the record runs of fall chinook led to several people asking, “If the salmon are doing so well, haven’t we done enough for salmon recovery?”
The quick answer is, “No. We’ve got a lot more to do!” But why is that? Because we know that conditions won’t always be so good. A big part of that is the ocean. Right now we are seeing boosts from a combination of all the salmon recovery work that has been done and some great ocean conditions. In recent years, sockeye and fall chinook encountered strong cool upwelling zones- full of fat-laden copepods- as they left the Columbia and entered the ocean. That gave them a massive survival boost in the early-ocean stage.
However, right now the Gulf of Alaska is unusually warm- 2 degrees C warmer than any other year going back to 1900. That, which means steelhead from the Yakima Basin that headed out to sea this year are facing challenging conditions. We’ll see if that causes a dip in returns over the next few years.
Cold water fat-rich copedpod favored by salmon
Image from http://www.arcodiv.org/watercolumn/copepod.html
Conditions in the ocean have always cycled, and salmon runs have followed them. We can measure these impacts by looking at the ratio of smolts that enter the ocean to the number of adults that return a few years later (a smolt to adult ratio, or SAR). We know SARS have cycles, and we can associate that with known ocean climate indicators, like El Nino years and the Pacific Decadal Oscillation (PDO). What we don’t know is if these cycles are steady, or will change in the future, in response to climate change and other drivers. Early indications are that the roughly decadal switches in ocean conditions associated with the PDO are occurring more often, maybe every 5 years…
So what can we do? Salmon recovery focus on increasing freshwater productivity- how many offspring reach the ocean for each adult that returns to spawn. There is little we can do directly to change ocean conditions. If we double freshwater productivity, and ocean survival drops in half, the two cancel each other out, and we don’t see any change. If ocean conditions drop further, we’ll actually see a drop in run size, despite all our success improving freshwater productivity. That can be discouraging until we remember that if freshwater hadn’t increased, runs would have dropped even further, or even disappeared…
But as strong as the influence of the ocean is, it isn’t the only driver. Freshwater production also varies significantly. Some of this is in response to salmon recovery work- removing passage barriers, restoring habitat conditions, improving how we run the Columbia’s dams, running effective hatcheries and much more- all areas where we are making real progress. But climate cycles also affect the freshwater part of samlon and steelhead’s life cycles. The last time we had drought conditions- which typically cause poor survival for smolts leaving the Yakima- was in 2005. In contrast, from 2011 through 2013 we had an exceptional series of wet, cool springs. When drought returns- as it inevitably will- smolt survival will drop. At the other extreme, intense rainfall events lead to floods that can scour out salmon, steelhead and bull trout redds- washing away eggs before they can develop. That can greatly reduce production in a given year and area- but those floods also can create and renew complex habitats, often increasing production in following years. We can work on restoring resilient habitats- where redds can be protected from high flows, and where cool water pockets serve as refuges in hot years. We cannot change the fact that there will be dry, hot years and scouring floods- and that scientists broadly agree that we may see more of each of these in the future.
So where does that leave us? Most of our Endangered Species Act listings for salmon and steelhead were made when both freshwater productivity and ocean survival were low. That focused a lot of effort on salmon recovery work, which we and all our partners are proud to be a part of. In good years, like these, we see the fruits of our labors, as fish show up in recently reopened habitat and commercial, tribal and recreational fisheries all thrive. But a few good years don’t mean much on their own. That’s why all the abundance goals in the Yakima Steelhead Recovery Plan are set as ten-year averages.
In the end, it’s how we do in the bad years that really matters. So enjoy the years like this- anglers, go fill your freezers, and parents, take your kids to go see fish piled up on the spawning grounds. But let’s remember that the real test will come when we sustain solid runs in the bad years. We’ve still got a lot of work to do before we can be confident we can pass that test- so celebrate the record runs, but remember that salmon recovery is a long-term commitment that needs all of our support!